A base station of a mobile communication system refers to a system for relaying electric waves of a portable terminal in a cell. The base station is generally installed on a roof of a building to relay electric waves of a portable terminal. Accordingly, base stations are present in units of cells, and the base stations controls transmission of signals, designation of a communication channel, and monitoring of a communication channel in units of cells, as well as an interface function between the portable terminal and a switch center.
The antennas employed in the base station are distributed due to presence of many control antennas which may be vertically or horizontally beam-tilted.
In addition, a small base station for improving communication quality while reducing frequency load is installed as a system for covering an area which is still smaller than the radius of the current existing mobile communication service. The base station is used to accommodate data traffic intensively generated in a small area. As a small base station can be installed in a building or a house, a shading area can be solved and a higher network and a convergence service can be realized.
However, because the small base station employed in the existing mobile communication system is configured such that main components mounted to the interior of the base station, for example, a main board, a power supply unit, an antenna, and a power amplifier are vertically stacked, there is a limit in reducing the entire size of the base station.
In particular, because the small base station according to the related art is configured such that a main board, a power supply unit and the like are installed on one board, the overall size of the main board become larger and heat emission of the power amplifier becomes problematic.